The present invention relates generally to neon light displays and is particularly concerned with a sealing assembly for sealing the conduits carrying high voltage wiring for supplying power to a neon light display through a mounting surface supporting the neon tubing.
Neon light displays are typically mounted on a back plate or wall surface and are energized by a high voltage supply on the other side of the mounting surface. The electrical wiring connecting the high voltage supply to the neon tube must therefore pass through the wall or mounting surface to connect to the neon tube electrodes.
The ends of the high voltage wires must be connected to the neon tube electrodes, and this connection must not be exposed. In our U.S. Pat. No. 5,008,787, a system for insulated support of neon lights was described, in which a glass insulation cup was used to shield the high voltage connection at the electrodes. The glass insulating cup slides over the exposed wire ends and is secured to the background surface, protecting and shielding the high voltage connection.
In order to connect through the background surface and building wall to a high voltage supply inside a building, the wiring must pass through a suitable opening to the background surface, and must be shielded from the elements as it passes through the background surface. Typically, a special glass housing or shell having a rim at one end, known as a PK housing, extends through a hole in the neon background surface or plate from the rear to the front side of the plate, and receives and encloses the horizontal end of the bent neon glass tube. The wiring extends through the PK housing and through a standard electrical wiring conduit connected to the other end of the PK housing and leading to the high voltage supply. A rubber boot is used to surround the rim of the PK housing and the bent neon glass tubing where it extends into the housing.
This known mounting and connecting assembly for high voltage wiring connections has a number of disadvantages. Firstly, the hole in the neon display back plate must be relatively large to receive the glass PK housing, typically around 1 15/16 inches in diameter. Secondly, the rubber boot is not suitable for outdoor use since it is not completely water tight and does not provide adequate protection against the elements. Thus, some water will typically leak into the connection with this arrangement if it is used outdoors.